WO2025145049A1 - Thrombus removal systems and associated methods - Google Patents

Abstract

The present technology relates to systems and methods for removing a thrombus from a blood vessel of a patient. In some embodiments, the present technology is directed to systems including an elongated catheter having a distal portion configured to be positioned within the blood vessel of the patient, a proximal portion configured to be external to the patient, and a lumen extending therebetween. The system can also include a fluid delivery mechanism coupled with a fluid lumen and configured to apply fluid to at least partially fragment the thrombus.

Description

THROMBUS REMOVAL SYSTEMS AND ASSOCIATED METHODS

PRIORITY CLAIM

[0001] This patent application claims priority to U.S. provisional patent application no. 63/615,197, titled “THROMBUS REMOVAL SYSTEMS AND ASSOCIATED METHODS,” and filed on December 27, 2023, and U.S. provisional patent application no. 63/615,736, titled “INTRODUCER CATHETER SYSTEMS AND METHODS,” and filed on December 28, 2023, which are both herein incorporated by reference in their entirety.

INCORPORATION BY REFERENCE

[0002] All publications and patent applications mentioned in this specification are herein incorporated by reference to the same extent as if each individual publication or patent application was specifically and individually indicated to be incorporated by reference.

FIELD

[0003] The present technology generally relates to medical devices and, in particular, to systems including aspiration and fluid delivery mechanisms and associated methods for removing a thrombus from a mammalian blood vessel.

BACKGROUND

[0004] Thrombotic material may lead to a blockage in fluid flow within the vasculature of a mammal. Such blockages may occur in varied regions within the body, such as within the pulmonary system, peripheral vasculature, deep vasculature, or brain. Pulmonary embolisms typically arise when a thrombus originating from another part of the body (e.g., a vein in the pelvis or leg) becomes dislodged and travels to the lungs.

[0005] Anti coagulation therapy is the current standard of care for treating pulmonary embolisms, but may not be effective in some patients. Additionally, conventional devices for removing thrombotic material may not be capable of navigating the tortuous vascular anatomy, may not be effective in removing thrombotic material, and/or may lack the ability to provide sensor data or other feedback to the clinician during the thrombectomy procedure. [0006] Existing thrombectomy devices operate based on simple aspiration which works sufficiently for certain clots but is largely ineffective for difficult, organized clots. Many patients presenting with deep vein thrombus (DVT) are left untreated as long as the risk of limb ischemia is low. In more urgent cases, they are treated with catheter-directed thrombolysis or lytic therapy to break up a clot over the course of many hours or days. More recently other tools like clot retrievers have been developed to treat DVT and pulmonary embolism (PE), but these tools are not being widely adopted because of their limited effectiveness and additional costs versus aspiration or the standard of case.

[0007] Blood loss is an undesirable result of thrombectomy. If the end of the catheter is not in contact with the clot when aspirating, blood is aspirated rather than clot. Positioning the distal end of the catheter adjacent to the clot is difficult. Fluoroscopy is used to help navigate the catheter to the clot. The clot is not easily distinguished from the surrounding anatomy. Contrast agent can be injected upstream of the clot to identify the margins of the clot. Patients can tolerate a limited amount of contrast agent. Other ways to determine the catheter is adjacent to clot are needed to help reduce blood loss.

SUMMARY OF THE DISCLOSURE

[0008] A system for removing thrombus from a patient, the system comprising: an elongated catheter having at least one aspiration lumen configured to remove thrombus material; an aspiration mechanism fluidly coupled to the aspiration lumen and configured to reduce pressure in the aspiration lumen; a pressure sensor configured to monitor a pressure inside the aspiration lumen; a valve disposed between the pressure sensor and the aspiration mechanism; and an electronic controller operatively coupled to the aspiration mechanism, the pressure sensor, and the valve, the electronic controller being configured implement a clot hunting mode in which the electronic controller: 1) controls the valve to open; 2) controls the aspiration mechanism to pull a preset volume of fluid into the aspiration lumen; 3) after pulling the preset volume of fluid, controls the valve to close; 4) monitors a pressure response within the aspiration lumen to determine if a clot is engaged with the elongated catheter.

[0009] In some aspects, the preset volume of fluid comprises 0-5ml.

[0010] In other aspects, the preset volume of fluid comprises 5- 10ml.

[0011] In some aspects, the electronic controller monitors the pressure response within a preset time period.

[0012] In some aspects, the preset time period comprises less than 1 second.

[0013] In some aspects, the preset time period comprises less than 2 seconds.

[0014] In other aspects, the preset time period comprises less than 3 seconds.

[0015] In one aspect, the preset time period comprises less than 5 seconds.

[0016] In other aspects, wherein, if the electronic controller determines that clot is engaged with the elongated catheter, the electronic controller is further configured to: 5) control the valve to open, and 6) control the aspiration mechanism to aspirate clot into the aspiration lumen. [0017] In some aspects, a vacuum level applied during step 2 is lower than a vacuum level applied during step 6.

[0018] In other aspects, a fluid delivery mechanism is configured to deliver one or more fluid streams into a distal end of the elongated catheter, wherein the system is further configured to control the fluid delivery mechanism to deliver fluid streams into the clot. [0019] In one aspect, wherein, if the electronic controller determines that clot is not engaged with the elongated catheter, the electronic controller is further configured to: 5) control the valve to open, and 6) control the aspiration mechanism to return the preset volume of fluid to the patient.

[0020] A system for removing thrombus is provided, the system comprising: an elongated catheter having at least one aspiration lumen configured to remove thrombus material; an aspiration mechanism fluidly coupled to the aspiration lumen and configured to reduce pressure in the aspiration lumen; a peristaltic pump coupled to the aspiration lumen; a pressure sensor configured to monitor a pressure inside the aspiration lumen; a valve disposed between the pressure sensor and the aspiration mechanism; and an electronic controller operatively coupled to the aspiration mechanism, the peristaltic pump, the pressure sensor, and the valve, the electronic controller being configured implement a clot hunting mode in which the electronic controller: 1) controls the peristaltic pump to pull a preset volume of fluid into the aspiration lumen; 2) after pulling the preset volume of fluid, monitor a pressure response within the aspiration lumen to determine if a clot is engaged with the elongated catheter.

[0021] In some aspects, the preset volume of fluid comprises 0-5ml.

[0022] In other aspects, the preset volume of fluid comprises 5- 10ml.

[0023] In one aspect, the electronic controller monitors the pressure response within a preset time period.

[0024] In other aspects, the preset time period comprises less than 1 second.

[0025] In some aspects, the preset time period comprises less than 2 seconds.

[0026] In other aspects, the preset time period comprises less than 3 seconds.

[0027] In some aspects, the preset time period comprises less than 5 seconds.

[0028] In additional aspects, if the electronic controller determines that clot is engaged with the elongated catheter, the electronic controller is further configured to: 5) control the valve to open, and 6) control the aspiration mechanism to aspirate clot into the aspiration lumen.

[0029] In some aspects, a vacuum level applied during step 2 is lower than a vacuum level applied during step 6. [0030] In one aspect, a fluid delivery mechanism is configured to deliver one or more fluid streams into a distal end of the elongated catheter, wherein the system is further configured to control the fluid delivery mechanism to deliver fluid streams into the clot.

[0031] In some aspects, if the electronic controller determines that clot is not engaged with the elongated catheter, the electronic controller is further configured to: 5) control the valve to open, and 6) control the aspiration mechanism to return the preset volume of fluid to the patient.

[0032] A method for removing thrombus is provided, comprising: introducing a distal portion of an elongated catheter into the body of a patient, the catheter including an aspiration lumen in fluid communication with the distal end for removal of thrombus; positioning a distal end of the catheter in the region of a target thrombus; pulling a preset volume of blood into the aspiration lumen; returning the preset volume of blood to the patient; during the pulling and/or returning steps: closing or opening a valve in the aspiration lumen; monitoring pressure at least in the aspiration lumen; and identifying engagement of the target thrombus with the distal end based on the monitored pressure and a valve state of the valve.

[0033] In one aspect, the preset volume of fluid comprises 0-5ml.

[0034] In some aspects, the preset volume of fluid comprises 5- 10ml.

[0035] In some aspects, the method includes monitoring the pressure over a preset time period.

[0036] In one aspect, the preset time period comprises less than 1 second.

[0037] In some aspects, the preset time period comprises less than 2 seconds.

[0038] In one aspect, the preset time period comprises less than 3 seconds.

[0039] In other aspects, the preset time period comprises less than 5 seconds.

[0040] In some aspects, if it is determined that the target thrombus is engaged, closing the valve, and aspirating the target thrombus into the aspiration lumen.

[0041] In one aspect, if it is determined that the target thrombus is not engaged, opening the valve, and returning the preset volume of blood to the patient.

[0042] A method of calculating cardiac output is provided, comprising: advancing a sheath or introducer catheter into the pulmonary vasculature of a patient; introducing a bolus of cold fluid into the heart and measuring a temperature response at a distal tip of the introducer catheter; measuring pressures in the heart and the pulmonary artery; and calculating cardiac output or index.

[0043] In some aspects, measuring the temperature response with the introducer catheter. [0044] In one aspect, the method comprises measuring the temperature response with a medical device advanced out of the introducer catheter. [0045] An introducer catheter system is provided, comprising: an elongate, steerable introducer catheter shaft adapted for insertion into a pulmonary artery of a subject;

[0046] an infusion port adapted to be disposed within the heart when a tip of the shaft is in the pulmonary artery, the infusion port being configured to infuse a bolus of fluid into the heart; at least one pressure sensor disposed on the catheter shaft, the pressure sensor being configured to continuously or periodically measure a pressure within the pulmonary artery and/or the heart; a fiber optic sensor configured to measure SvO2; a thermistor on a distal portion of the catheter shaft, the thermistor being configured to measure changes in blood temperature; and at least one controller configured to calculate at least one of thermodilution (flow), cardiac output, or cardiac index.

[0047] An introducer catheter system is provided, comprising: an elongate, steerable introducer catheter shaft adapted for insertion into a pulmonary artery of a subject; a heated coil adapted to be disposed within the heart when a tip of the shaft is in the pulmonary artery, the heated coil being configured to heat blood in the heart; at least one pressure sensor disposed on the catheter shaft, the pressure sensor being configured to continuously or periodically measure a pressure within the pulmonary artery and/or the heart; a fiber optic sensor configured to measure SvO2; a thermistor on a distal portion of the catheter shaft, the thermistor being configured to measure changes in blood temperature; and at least one controller configured to calculate at least one of thermodilution (flow), cardiac output, or cardiac index.

BRIEF DESCRIPTION OF THE DRAWINGS

[0048] The novel features of the invention are set forth with particularity in the claims that follow. A better understanding of the features and advantages of the present invention will be obtained by reference to the following detailed description that sets forth illustrative embodiments, in which the principles of the invention are utilized, and the accompanying drawings of which:

[0049] FIGS. 1-1L illustrate various views of a portion of a thrombus removal system including a distal portion of an elongated catheter configured in accordance with an embodiment of the present technology.

[0050] FIGS. 2A-2E illustrate plan views of various configurations of irrigation ports and fluid streams of a thrombus removal system according to embodiments of the present technology.

[0051] FIGS. 3A-3H illustrate an elevation view of various configurations of irrigation ports of a thrombus removal system according to embodiments of the present technology. [0052] FIGS. 4A-4E illustrate an elevation view of various configurations of irrigation ports and fluid streams of a thrombus removal system according to embodiments of the present technology.

[0053] FIG. 5 is a thrombectomy system.

[0054] FIGS. 6A-6D are a method of detecting if a clot is engaged with a thrombectomy catheter.

[0055] FIG. 7 is a thrombectomy system.

[0056] FIGS. 8A-8B are examples of a thrombectomy system.

[0057] FIGS. 9A-9D illustrate various embodiments of an introducer catheter that can include one or more sensors or features for measuring thermodilution and calculating cardiac output or index.

[0058] FIG. 10 is an example of an introducer catheter medical device inserted into a patient for calculating cardiac index or output.

DETAILED DESCRIPTION

[0059] This application is related to disclosure in International Application No. PCT/US2021/020915, filed March 4, 2021 (the ‘915 application), the disclosure of which is incorporated by reference herein for all purposes. The ‘915 application describes general mechanisms for capturing and removing a clot. By example, the catheter may include a capture element such as an auger to break up and draw in a clot material into an aspiration lumen. In another example, multiple fluid streams are directed toward the clot to fragment the material.

[0060] The present technology is generally directed to thrombus removal systems and associated methods. A system configured in accordance with an embodiment of the present technology can include, for example, an elongated catheter having a distal portion configured to be positioned within a blood vessel of the patient, a proximal portion configured to be external to the patient, a fluid delivery mechanism configured to fragment the thrombus with pressurized fluid, an aspiration mechanism configured to aspirate the fragments of the thrombus, and one or more lumens extending at least partially from the proximal portion to the distal portion..

[0061] The terminology used in the description presented below is intended to be interpreted in its broadest reasonable manner, even though it is being used in conjunction with a detailed description of certain specific embodiments of the present technology. Certain terms may even be emphasized below; however, any terminology intended to be interpreted in any restricted manner will be overtly and specifically defined as such in this Detailed Description section. Additionally, the present technology can include other embodiments that are within the scope of the examples but are not described in detail with respect to the figures.

[0062] Reference throughout this specification to "one embodiment" or "an embodiment" means that a particular feature, structure, or characteristic described in connection with the embodiment is included in at least one embodiment of the present technology. Thus, the appearances of the phrases "in one embodiment" or "in an embodiment" in various places throughout this specification are not necessarily all referring to the same embodiment. Furthermore, the particular features or characteristics may be combined in any suitable manner in one or more embodiments.

[0063] Reference throughout this specification to relative terms such as, for example, "generally," "approximately," and "about" are used herein to mean the stated value plus or minus 10%.

[0064] Although some embodiments herein are described in terms of thrombus removal, it will be appreciated that the present technology can be used and/or modified to remove other types of emboli that may occlude a blood vessel, such as fat, tissue, or a foreign substance. Additionally, although some embodiments herein are described in the context of thrombus removal from a pulmonary artery (e.g., pulmonary embolectomy), the technology may be applied to removal of thrombi and/or emboli from other portions of the vasculature (e.g., in neurovascular, coronary, or peripheral applications). Moreover, although some embodiments are discussed in terms of maceration of a thrombus with a fluid, the present technology can be adapted for use with other techniques for breaking up a thrombus into smaller fragments or particles (e.g., ultrasonic, mechanical, enzymatic, etc.).

[0065] The headings provided herein are for convenience only and do not interpret the scope or meaning of the claimed present technology.

Systems for Thrombus Removal

[0066] As provided above, the present technology is generally directed to thrombus removal systems. Such systems include an elongated catheter having a distal portion positionable within a blood vessel of the patient (e.g., an artery or vein), a proximal portion positionable outside the patient's body, a fluid delivery mechanism configured to fragment the thrombus with pressurized fluid, an aspiration mechanism configured to aspirate the fragments of the thrombus, and one or more lumens extending at least partially from the proximal portion to the distal portion. In some embodiments, the systems herein are configured to engage a thrombus in a patient's blood vessel, break the thrombus into small fragments, and aspirate the fragments out of the patient's body. The pressurized fluid streams (e.g., jets) function to cut or macerate thrombus, before, during, and/or after at least a portion of the thrombus has entered the aspiration lumen or a funnel of the system. Fragmentation helps to prevent clogging of the aspiration lumen and allows the thrombus removal system to macerate large, firm clots that otherwise could not be aspirated. As used herein, “thrombus” and “embolism” are used somewhat interchangeably in various respects. It should be appreciated that while the description may refer to removal of “thrombus,” this should be understood to encompass removal of thrombus fragments and other emboli as provided herein.

[0067] According to embodiments of the present technology, a fluid delivery mechanism can provide a plurality of fluid streams (e.g., jets) to fluid apertures of the thrombus removal system for macerating, cutting, fragmenting, pulverizing and/or urging thrombus to be removed from a proximal portion of the thrombus removal system. The thrombus removal system can include an aspiration lumen extending at least partially from the proximal portion to the distal portion of the thrombus removal system that is adapted for fluid communication with an aspiration pump (e.g., vacuum source). In operation, the aspiration pump may generate a volume of lower pressure within the aspiration lumen near the proximal portion of the thrombus removal system, urging aspiration of thrombus from the distal portion.

[0068] FIG. 1 illustrates a distal portion 10 of a thrombus removal system according to an embodiment of the present technology. FIG. 1 A Section A-A illustrates an elevation sectional view of the distal portion. The example section A-A in FIG. 1 A depicts a funnel 20 that is positioned at the distal end of the distal portion 10, the funnel adapted to engage with thrombus and/or a tissue (e.g., vessel) wall to aid in thrombus fragmentation and/or removal. The funnel can have a variety of shapes and constructions as would be understood by one of skill from the description herein. The example section A-A in FIG. 1 A depicts a double walled thrombus removal device construction having an outer wall/tube 40 and an inner wall/tube 50. An aspiration lumen 55 is formed by the inner wall 50 and is centrally located. A generally annular volume forms at least one fluid lumen 45 between the outer wall 40 and the inner wall 50. The fluid lumen 45 is adapted for fluid communication with the fluid delivery mechanism. One or more apertures (e.g., nozzles, orifices, or ports) 30 are positioned in the thrombus removal system to be in fluid communication with the fluid lumen 45 and an irrigation manifold 25. In operation, the ports 30 are adapted to direct (e.g., pressurized) fluid toward thrombus that is engaged with the distal portion 10 of the thrombus removal system.

[0069] In various embodiments, the system can have an average flow velocity within the fluid lumen of up to 20 m/s to achieve consistent and successful aspiration of clots. In some embodiments, the fluid source itself can be delivered in a pulsed sequence or a preprogrammed sequence that includes some combination of pulsatile flow and constant flow to deliver fluid to the jets. In these embodiments, while the average pulsed fluid velocity may be up to 20 m/s, the peak fluid velocity in the lumen may be up to 30 m/s or more during the pulsing of the fluid source. In some embodiments, the jets or apertures are no smaller than 0.0100” or even as small as 0.008” to avoid undesirable spraying of fluid. In some embodiments, the system can have a minimum vacuum or aspiration pressure of 15 inHg, to remove target clots after they have been macerated or broken up with the jets described above.

[0070] The thrombus removal system can be sized and configured to access and remove thrombi in various locations or vessels within a patient’s body. It should be understood that while the dimensions of the system may vary depending on the target location, generally similar features and components described herein may be implemented in the thrombus removal system regardless of the application. For example, a thrombus removal system configured to remove pulmonary embolism (PE) from a patient may have an outer wall/tube with a size of approximately 11-13 Fr, or preferably 12 Fr, and an inner wall/tube with a size of 7-9 Fr, or preferably 8 Fr. A deep vein thrombosis (DVT) device, on the other hand, may have an outer wall/tube with a size of approximately 9-11 Fr, or preferably 10 Fr, and an inner wall/tube with a size of 6-9 Fr, or preferably 7.5 Fr. Applications are further provided for ischemic stroke and peripheral embolism applications.

[0071] Section B-B of FIG. IB illustrates in plan view a portion of the thrombus removal system that is proximal to the funnel and irrigation manifold. Section B-B depicts an outer wall 140, an inner wall 150, an aspiration lumen 155 and a fluid lumen 145. In some embodiments, in cross-section the aspiration lumen 155 is generally circular and the fluid lumen 145 is generally annular in shape (e.g., cross-section 70). It will be appreciated that alternative constructions and/or arrangements of the inner wall 150 and the outer wall 140 produce variations in cross-sectional shape of the aspiration and fluid lumens 155 and 145. For example, the inner wall 150 can be shaped to form an aspiration lumen 155 that, in crosssection, is generally oval, circular, rectilinear, square, pentagonal, or hexagonal. The inner and outer walls 150 and 140 can be shaped and arranged to form a fluid lumen 145 that, in cross-section, is generally crescent-shaped, diamond shaped, or irregularly shaped. For example, referring to FIG. 1C Section B-B, the region between the inner wall 150 and the outer wall 140 can include one or more wall structures 165 that form respective fluid lumens 145 (e.g., as in cross-section 80). The wall structures 165 can be formed by lamination between the outer and inner walls 140 and 150, or by a multi -lumen extrusion that forms a plurality of the wall structures.

[0072] Section B-B of FIGS. 1D-1H illustrate additional examples of a portion of the thrombus removal system that is proximal to the funnel and irrigation manifold. Similar to the embodiments described above, the portion in these examples can include an outer wall 140, an inner wall 150, and an aspiration lumen 155. Additionally, the illustrated portion of the thrombus removal system can include a middle wall 170 disposed between the outer wall 140 and the inner wall 150. The middle wall 170 enables further segmentation of the annular space between the inner wall and outer wall into a plurality of distinct fluid lumens and/or auxiliary lumens. For example, referring to FIG. ID, the middle wall can be generally hexagon shaped, and the annular space can include a plurality of fluid lumens 145a- 141 and a plurality of auxiliary lumens 175a-175f. As shown in FIG. ID, the fluid lumens can be formed by some combination of the outer wall 140 and the middle wall 170, or between the middle wall 170, the inner wall 150, and two of the auxiliary lumens. For example, fluid lumen 145a is formed in the space between outer wall 140 and middle wall 170. However, fluid lumen 145g is formed in the space between middle wall 170, inner wall 150, auxiliary lumen 175a, and auxiliary lumen 175b. Generally, the fluid lumens are configured to carry a flow of fluid such as saline from a saline source of the system to one or more ports/apertures/orifices of the system. The auxiliary lumens can be configured for a number of functions. In some embodiments, the auxiliary lumens can be coupled to the fluid/saline source and to the apertures to be used as additional fluid lumens. In other embodiments, the auxiliary lumens can be configured as steering ports and can include a guide wire or steering wire within the lumen for steering of the thrombus removal system. Additionally, in other embodiments, the auxiliary lumens can be configured to carry electrical, mechanical, or fluid connections to one or more sensors. For example, the system may include one or more electrical, optical, or fluid based sensors disposed along any length of the system. The sensors can be used during therapy to provide feedback for the system (e.g., sensors can be used to detect clogs to initiate a clog removal protocol, or to determine the proper therapy mode based on sensor feedback such as jet pulse sequences, aspiration sequences, etc.). The auxiliary ports can therefore be used to connect to the sensors, e.g., by electrical connection, optical connection, mechanical/wire connection, and/or fluid connection. It is also contemplated that the fluid and auxiliary lumens can be configured to carry and deliver other fluids, such as thrombolytics or radio-opaque contrast injections to the target tissue site during treatment. [0073] It should be understood that in some embodiments, all the fluid lumens are fluidly connected to all of the jets or apertures of the thrombus removal device. Therefore, when a flow of fluid is delivered from the fluid lumen(s) to the jets, all jets are activated with a jet of fluid at once. However, it should also be understood that in some embodiments, the fluid lumens are separate or distinct, and these distinct fluid lumens may be fluidly coupled to one or more jets but not to all jets of the device. In these embodiments, a subset of the jets can be controlled by delivering fluid only to the fluid lumens that are coupled to that subset of jets. This enables additional functionality in the device, in which specific jets can be activated in a user defined or predetermined order.

[0074] In various embodiments, the fluid pressure is generated at the pump (in the console or handle). The fluid is accelerated as it exits the ports at the distal end and is directed to the target clot. In this way a wider variety of cost-effective components can be used to form the catheter while still maintaining a highly-effective device for clot removal. Additional details are provided below.

[0075] Section B-B of FIG. IE illustrates another embodiment of the portion of the thrombus removal system that is proximal to the funnel and irrigation manifold. Similar to the embodiment of FIG. ID, this embodiment also includes a middle wall 170. However, the middle wall in this example is generally square shaped, facilitating the formation of fluid lumens 145a-145k and auxiliary lumens 175a-175d. The example illustrated in section B-B of FIG. IF is similar to that of the embodiment of FIG. IE, however this embodiment includes only fluid lumens 145a-145d. The fluid lumens 145e-145k from the embodiment of FIG. IE are not used as fluid lumens in this embodiment. They can be, for example, empty lumens, vacuum, filled with an insulative material, and/or filled with a radio-opaque material or any other material that may help visualize the thrombus removal system during therapy. The embodiment IF includes the same four auxiliary reports as illustrated and described in the embodiment of FIG. IE.

[0076] Section B-B of FIG. 1G illustrates another example of a portion of the thrombus removal system that is proximal to the funnel and irrigation manifold. Similar to the embodiments described above, the illustrated portion of the thrombus removal system can include a middle wall 170 disposed between the outer wall 140 and the inner wall 150. However, this embodiment includes four distinct fluid lumens 145a-145d formed by wall structures 165. As with the embodiment of FIG. 1C, the wall structures 165 can be formed by lamination between the outer and inner walls 140 and 150, or by a multi-lumen extrusion that forms a plurality of the wall structures. As shown, this embodiment can include a pair of auxiliary lumens 175a and 175b, which can be used, for example, for steering or for sensor connections as described above.

[0077] Section B-B of FIG. 1H is another similar embodiment in which the middle wall and outer wall can be used to form fluid lumens 145a and 145b. Auxiliary lumens 175a and 175b can be formed in the space between the middle wall and the inner wall. It should be understood that the middle wall can contact the outer wall to create independent fluid lumens 145a and 145b. However, in other embodiments, it should be understood that the middle wall may not contact the outer wall, which would facilitate a single annular fluid lumen, such as is shown by fluid lumen 145 in Section B-B of FIG. II. In another embodiment, as shown in Section B-B of FIG. 1 J, the inner wall 150 and the outer wall 140 may not be concentric, which facilitates formation of an annular space and/or fluid lumen 145 that is thicker or wider on one side of the device relative to the other side. As shown in FIG. 1 J, a distance between the exemplary outer wall 140 and inner wall at the top (e.g., 12 o’clock) portion of the device is larger than a distance between the outer wall and inner wall at the bottom (e.g., 6 o’clock) portion of the device.

[0078] Section C-C of FIG. IK illustrates in plan view a portion of the thrombus removal system comprising an irrigation manifold 225. Section C-C depicts an outer wall 240, an inner wall 250, a fluid lumen 245, an aspiration lumen 255, and ports 230 for directing respective fluid streams 210.

[0079] Detail View 101 of FIG. IL illustrates a section view in elevation of a portion of the irrigation manifold 25 that includes a plurality of ports 230 that are formed within an inner wall 250. In some embodiments, a thickness of one or more walls of the thrombus removal system may be varied along its axial length and/or its circumference. As shown in Detail View 101, inner wall 250 has a first thickness 265 in a region 250 that is proximal to the irrigation manifold 25, and a second thickness 270 in a region 235 that includes the ports 230. In some embodiments, the second thickness 270 is greater than the first thickness 265. The first thickness 265 can correspond to a general wall thickness of the inner wall 50 and/or of the outer wall 40, which can be from about 0.10 mm to about 0.60 mm, or any value within the aforementioned range. The second thickness 270 can be from about 0.20 mm to about 0.70 mm, from about 0.70 mm to about 0.90 mm, or from about 0.90 mm to about 1.20 mm. The second thickness 270 can be any value within the aforementioned range. The dimension of the second thickness 270 can be selected to provide a fluid path through the ports 230 that produces a generally laminar flow for a fluid stream that is directed therethrough, when the fluid delivery mechanism supplies fluid via the fluid lumen 245 at a typical operating pressure. Such operating pressure can be from about 10 psi to about 60 psi, from about 60 psi to about 100 psi, or from about 100 psi to about 150 psi. The operating pressure of the fluid delivery mechanism can be any value within the aforementioned range of values. In some embodiments, the fluid delivery mechanism is operated in a high pressure mode, having a pressure from about 150 psi to about 250 psi, from about 250 psi to about 350 psi, from about 350 psi to about 425 psi, or from about 425 psi to about 500 psi. The operating pressure of the fluid delivery mechanism in the high pressure mode can be any value within the aforementioned range of values.

[0080] The manifold is configured to increase a fluid pressure and/or flow rate of the fluid. When fluid is provided by the fluid delivery mechanism to the fluid lumen(s) at a first pressure and/or a first flow rate, the manifold is configured to increase the pressure of the fluid to a second pressure and/or is configured to increase the flow rate of the fluid to a second flow rate. The second pressure and/or second fluid rate can be higher than the first pressure and/or first flow rate. As a result, the manifold can be configured to increase the relatively low operating pressures and/or flow rates generated by the fluid delivery mechanism to the relatively high pressures and/or high flow rates generated by the ports/fluid streams.

[0081] In some embodiments, a profile (cross-sectional dimension) of a port 230 varies along its length (e.g., is non-cylindrical). A variation in the cross-sectional dimension of the port may alter and/or adjust a characteristic of fluid flow along the port 230. For example, a reduction in cross-sectional dimension may accelerate a flow of fluid through the port 230 (for a given volume of fluid). In some embodiments, a port 230 may be conical along its length (e.g., tapered), such that its smallest dimension is positioned at the distal end of the port 230, where distal is with respect to a direction of fluid flow.

[0082] In some embodiments, the port 230 is formed to direct the fluid flow along a selected path. FIGS. 2A-2E illustrate various embodiments of arrangements of ports 230 for directing respective fluid streams 210. In some embodiments, such as those shown in FIGS. 2A and 2B, at least two ports 230 are arranged to produce (e.g., respective) fluid streams 210 that intersect at an intersection region 237 of the thrombus removal system. An intersection region 237 can be a region of increased fluid momentum and/or energy transfer, which multiply with respect to individual fluid streams that are not directed to combine at the intersection. The increased fluid momentum and/or energy transfer at an intersection may advantageously fragment thrombus more efficiently and/or quickly. As described above, the fluid streams can be configured to accelerate and cause cavitation and/or other effects to further add to breaking up of the target clot. In some embodiments, an intersection region can be formed from at least 2, at least 3, at least 4, at least 5, at least 6, at least 7, at least 8, at least 9, or at least 10 fluid streams 210. An intersection region can be generally near a central axis 290 of the thrombus removal system (e.g., 237), or away from the central axis (e.g., 238 and 239 in the embodiment of FIG. 2D). In some embodiments, at least two intersection regions (e.g., 238 and 239) are formed. In some embodiments, one or more ports 230 are arranged to direct a fluid stream 210 along an oblique angle with respect to the central axis of the thrombus removal system. An operating pressure of the fluid delivery mechanism may be selected to approach a minimum targeted fluid velocity for a fluid stream 210 that is delivered from a port 230. The targeted fluid velocity for a fluid stream 210 can be about 5 meters/second (m/s), about 8 m/s, about 10 m/s, about 12 m/s, or about 15 m/s. Additionally, the targeted fluid velocities in some embodiments can be in the range above 15m/s to up tol50 m/s. At these higher velocities (e.g. above 15m/s, or alternatively above 20m/s), the fluid streams may be configured to generate cavitation in a target thrombus or tissue. It has been found that with fluid exiting from the ports to these flow rates a cavitation effect can be created in the focal area of the intersecting or colliding fluid streams, or additionally at a boundary of one or more of the fluid streams. While the exact specifications may change based on the catheter size, in general, at least one of the fluid streams should be accelerated to such a high velocity to create cavitation as described in detail below. The targeted fluid velocity for fluid stream 210 can be any value within the range of aforementioned values. In some embodiments, at least two ports 230 are adapted to deliver respective fluid streams at different fluid velocities (i.e. speed and direction), for a given pressure of the fluid delivery mechanism. In some embodiments, at least two ports 230 are adapted to deliver respective fluid streams at the substantially the same fluid velocities, for a given pressure of the fluid delivery mechanism. In some embodiments, one port is adapted to deliver fluid at high velocity and the respective one or more other ports is adapted to deliver fluid at relatively lower velocities. Advantageously, an increased cross-sectional area of the fluid lumen 145 reduces a required operating pressure of the fluid delivery mechanism to achieve a targeted fluid velocity of the fluid streams.

[0083] In some embodiments, the fluid streams are configured to create angular momentum that is imparted to a thrombus. In some examples, angular momentum is imparted on the thrombus by application of a) at least one fluid stream 210 that is directed at an oblique angle from a port 230, and/or b) at least two fluid streams 210 that have different fluid velocities. For example, fluid streams that cross near each other but do not necessarily intersect may create a “swirl” or rotational energy on the clot material. Advantageously, angular momentum produced in a thrombus may impart a (e.g., centrifugal) force that assists in fragmentation and removal of the thrombus. Rotating of the clot may enhance delivery of the clot material to the jets. By example, with a large, amorphous clot the soft material may be easily aspirated or broken up by the fluid streams whereas tough fibrin may be positioned away from the fluid streams. Rotating or swirling of the clot moves the material around so the harder clot material is presented to the jets. The swirling may also further break up the clot as it is banged inside the funnel.

[0084] Referring to FIGS. 3A-3H, ports 330 can be arranged along various axial positions of the thrombus removal system. The thrombus removal system can include a flow axis 305 that is aligned with a general direction (e.g., distal-to-proximal) of flow for fluid that is aspirated therein. In some embodiments, a position of a port 330 comprises a) near a base of, b) in a middle portion of, c) in a distal portion of, or d) proximal to, a funnel portion 320 of the thrombus removal system. In some embodiments, at least two ports 330 are aligned along flow axis 305. In some embodiments, at least two ports 330 are arranged at a different axial and/or angular positions along the flow axis 305. In some embodiments, at least two ports 330 are arranged (e.g., along a perimeter of the thrombus removal system) along a given axial position of the flow axis 305.

[0085] FIGS. 4A-4E illustrate various configurations of a thrombus removal system 400, including a thrombus removal device, 402, a vacuum source and cannister 404, and a fluid source 406. In some embodiments, the vacuum source and cannister and the fluid source are housed in a console unit that is detachably connected to the thrombus removal device. A fluid pump can be housed in the console, or alternatively, in the handle of the device. The console can include one or more CPUs, electronic controllers, or microcontrollers configured to control all functions of the system. The thrombus removal device 402 can include a funnel 408, a flexible shaft 410, a handle 412, and one or more controls 414 and 416. For example, in the embodiment shown in FIG. 4 A, the device can include a finger switch or trigger 414 and a foot pedal or switch 416. These can be used to control aspiration and irrigation, respectively. Alternatively, as shown in the embodiment of FIG. 4B, the device can include only a foot switch 414, which can be used to control both functions, or in FIG. 4C, the device can include only an overpedal 416, also used to control both functions. It is also contemplated that an embodiment could include only a finger switch to control both aspiration and irrigation functions. As shown in FIG. 4A, the vacuum source can be coupled to the aspiration lumen of the device with a vacuum line 418. Any clots or other debris removed from a patient during therapy can be stored in the vacuum cannister 404. Similarly, the fluid source (e.g., a saline bag) can be coupled to the fluid lumens of the device with a fluid line 420. [0086] Still referring to FIG. 4A, electronics line 422 can couple any electronics/sensors, etc. from the device to the console/controllers of the system. The system console including the CPUs/electronic controllers can be configured to monitor fluid and pressure levels and adjust them automatically or in real-time as needed. In some embodiments, the CPUs/electronic controllers are configured to control the vacuum and irrigation as well as electromechanically stop and start both systems in response to sensor data, such as pressure data, flow data, etc.

[0087] In FIG. 4D, a system assembly is shown including a funnel 408 and a flexible shaft 410 of a thrombus removal device inserted into a steerable introducer catheter 31. A hub assembly such as a Touhy Borst is shown which can provide access for a medical device into the steerable introducer catheter and include an injection port for fluidic connection to the contrast injector 424. In this embodiment, injection of contrast from the injector 424 into the hub assembly provides the contrast agent into the annular space between the introducer catheter 31 and the thrombus removal device (e.g., the shaft of the thrombus removal device). [0088] FIG. 4E shows the funnel 408 of the thrombus removal device axially disposed out of a distal end of the introducer catheter 31. In this example, contrast delivered by the injector 424 into the annular space can still be delivered into the patient, even when the funnel is in a deployed configuration. In some examples, the funnel can disperse the contrast agent as it’s delivered past the funnel from the annular space.

[0089] As is described above, aspiration occurs down the central lumen of the device and is provided by a vacuum pump in the console. The vacuum pump can include a container that collects any thrombus or debris removed from the patient.

[0090] FIG. 5 is another example of a thrombectomy system 500 that can include a thrombectomy device 501, an introducer sheath 511, and a thrombectomy console 502. The device 501 can include a catheter shaft 503, an expandable funnel 505 at a distal end of the shaft, and an aspiration lumen within the catheter shaft for applying vacuum from the console 502 to the expandable funnel 505 of the device. The device can further include a handle 507 for use by a user to control operation of the thrombectomy device. The handle is provides various connections to the console, including an aspiration line 504 coupled to the aspiration lumen in the catheter shaft and an irrigation line 506 coupled to a fluid line or lumen for delivery of fluid from saline source 508 to one or more jets or irrigation ports at a distal end of the thrombectomy device. Additionally, the handle provides a sensor wire 510 for coupling a sensor within the thrombectomy system (e.g., in the thrombectomy device, or in the introducer sheath) to the console 502. The handle can further include a guidewire or auxiliary port 512 for gaining access to the aspiration lumen of the device, such as for introducing a guidewire into the catheter and/or introducing other fluids into the aspiration lumen.

[0091] The device 501 can be introduced into the patient with an introducer sheath 511 which can include a handle and a sheath shaft. The introducer sheath can include a pressure sensor for measuring pressure in the patient (coupled to the console with sensor wire 512) and a flush line 513 for introducing fluid into the annular space between the introducer sheath and the thrombectomy catheter (e.g., saline, contrast, etc.). A dilator 514 can be introduced into the introducer sheath to assist in gaining access to the patient anatomy.

[0092] The console 502 can include a display 516 for providing information to a user on a given procedure, a saline source 508 coupled to the irrigation line of the catheter, and a source of vacuum 518 coupled to the aspiration line of the catheter. The vacuum source can be fluidly coupled to a collection cannister 520 which can include an optional or removable clot trap 522 for capturing removed clot and/or separating blood from removed clot. The console can also include one or more electrical connections to a switch or electronics line of the catheter (e.g., the sensor wire 510).

Clog Engagement Detection

[0093] In one embodiment, a method for determining if the distal end of the thrombectomy catheter is adjacent to the clot is to perfuse a liquid such as a saline through a large lumen in the catheter and simultaneously monitor the pressure of the fluid. For example, saline can be introduced into the thrombectomy device aspiration lumen in the system of FIG. 5 through the auxiliary or guidewire lumen 512. When the distal end of the catheter is open to flow, the pressure will be low. When the distal end of the catheter is very near or engaged with the clot, the pressure will increase. Once the distal end of the catheter is engaged with the clot, aspiration may be initiated with less blood loss.

[0094] FIGS. 6A-6D illustrate this technique with an aspiration device 601 having a catheter shaft 603 with an aspiration lumen therein.

[0095] Referring to FIG. 6A, blood is aspirated when suction is applied to the proximal end of the catheter shaft (e.g., with the console) and the distal end of the catheter is not engaged with the clot. In FIG. 6B, clot is aspirated when suction is applied to the proximal end of the catheter and the distal end of the catheter shaft is engaged with the clot.

[0096] According to one aspect of the disclosure, in FIG. 6C, saline can be injected through the catheter shaft (such as into the aspiration lumen via the guidewire or auxiliary port described above), and the pressure of the fluid in the aspiration lumen can be measured. Aspiration is turned off when saline is injected into the aspiration lumen. The measured fluid pressure is low (e.g., below an engagement threshold) when fluid is injected into the proximal end of the catheter and the distal end of the catheter is not obstructed, since the fluid is allowed to flow out of the catheter distal end freely.

[0097] In FIG. 6D, measured pressure increases when fluid is injected into the proximal end of the catheter and the distal end of the catheter is in close proximity or engaged with the clot. If the measured fluid column pressure increases above an engagement threshold, then the system or console can indicate to a user that a clot is engaged, and aspiration can begin. In some aspects, aspiration can be automatically engaged when the engagement threshold is exceeded to immediately remove the clot with aspiration.

[0098] FIG. 7 represents a thrombectomy system which can include all the features of the system 500 described above. Referring to FIG. 7, the system can operate in a clot hunting mode in which a small preset small volume (e.g., 0-5ml, 5-10ml, 10-15ml, 15-20ml, 20-25ml, 0-10ml, 0-15ml, 0-20ml, 0-25ml) of blood is aspirated into the aspiration lumen of the device, but not removed from the device into the clot catcher. For example, the volume of blood can be pulled into the catheter shaft, but not enough blood is aspirated to reach the collection cannister or console. It is noted that this volume can vary depending on the length of the catheter and diameter of the aspiration lumen, but in general it is envisioned that only a small volume of blood is pulled into the catheter shaft itself. In some embodiments, the vacuum source can aspirate or pull at a fraction of full vacuum power (e.g., up to 10, 20, 30, 40, 50, 60% of full power) for a short period of time (e.g., 0-5 seconds) to achieve the aspiration of the small volume (5 -10ml) of blood into the aspiration lumen.

[0099] The system can continuously monitor the pressure of the aspiration line during the clot hunting procedure (e.g., with the pressure sensor(s) in the device). Once the preset small volume of blood has been aspirated into the aspiration lumen, a pinch valve between the vacuum source and the distal end of the aspiration lumen can be closed or clamped off (e.g., a pinch valve located along a length of aspiration line 504, and the pressure within the aspiration lumen can be monitored. If the pressure within the aspiration lumen quickly rebounds back towards atmospheric + blood pressure (e.g., 15 psi), then the system is likely not engaged with clot. The system can monitor the time it takes for the pressure to rebound. For example, if the pressure rebounds within a preset time period, such as within Is, within 2s, within up to 5s, then the system can determine no clot is engaged. However, if the pressure within the aspiration lumen does not rebound within the preset time period, then the system is likely engaged with clot. The system monitors to see if the vacuum remains stable or more quickly returns to atmospheric. Based on the rate of pressure change (aka rebound) and/or pressure in the lumen with successive cycles the system detects clot engagement. [0100] Once the preset small volume of blood has been aspirated into the lumen, the system can immediately return (push) the preset small volume of blood back into the patient. In some aspects, this can include reversing the vacuum source to push on the aspiration line, which therefore pushes the blood out of the aspiration lumen and back into the patient. In some embodiments, this pushing or return can occur for the same or similar amount of time as the system pulled or aspirated the blood into the line (e.g., 0-5 seconds).

[0101] In an alternative embodiment of FIG. 7, instead of using the vacuum source to pull the preset small volume into the aspiration lumen, a syringe or other pull/push mechanism can be coupled to the aspiration lumen of the catheter (such as with the guidewire or auxiliary lumen/access described above). For example, a syringe could be coupled to the aspiration lumen and used to pull/push the preset small volume of blood into the catheter for pressure monitoring.

[0102] In yet another embodiment, shown in FIGS. 8A-8B, a peristaltic pump 830 separate from the vacuum source could be coupled to the aspiration lumen of the catheter. The system can otherwise include the same components as described above in FIG. 5. This could be connected via the guidewire or auxiliary lumen/access described above.

[0103] In the embodiment of FIG. 8A, the peristaltic pump 830 can be controlled to pull the preset small volume of blood into the aspiration lumen, and then return the preset small volume to the patient as described above. The embodiment of FIG. 8 A can perform the same method/technique as described above in FIG. 7, instead using the peristaltic pump instead of the vacuum source.

[0104] In the embodiment of FIG. 8B, the peristaltic pump 830 can further be coupled to a flush line of the introducer sheath. In this embodiment, the peristaltic pump can continuously pull blood from the patient into the aspiration lumen and return blood simultaneously to the patient via the flush line in the introducer sheath during the clot hunting procedure. In some aspects, the blood can be filtered prior to being returned to the patient. As with the embodiments above, pinching or clamping a valve in the aspiration lumen and monitoring the pressure (e.g., the rebound) in the aspiration lumen can allow the system to determine if a clot is engaged with the catheter or not. Once a clot is detected or engaged with the system, the system can use the vacuum source from the console to pull aspiration into the lumen of the device to remove clot from the patient.

Systems for determining Cardiac Index or Cardiac Input

[0105] FIGS. 9A-9B illustrate a vascular access and treatment system 100 that can include an introducer catheter 102 and a medical device 104 disposed within a lumen of the introducer catheter. The introducer catheter can include an elongate, steerable, flexible shaft and a distal end 103 at the end of one or more lumens that runs along the shaft of the introducer catheter. The introducer catheter can include one or more sensors 105 disposed along, in, or within the shaft 101, including but not limited to pressure sensors, flow sensors, electrical sensors (electrodes), or any other sensor useful for measuring patient parameters during an intravascular procedure. In some embodiments, the introducer catheter can include all the functionality and sensors of a Swan-Ganz or pulmonary artery catheter (PAC), allowing for direct, simultaneous measurements of pressures in the right atrium, right ventricle, pulmonary artery, and the filling pressure of the left atrium. In some aspects, the distal end of the catheter can include an inflatable member or ballon 107 which can be used to anchor or hold the distal end 103 of the introducer catheter in place, such as while measuring cardiac index or output (e.g., in the pulmonary artery).

[0106] In some embodiments, the introducer catheter can be approximately 60 to 110 cm in length, to enable measurements within the pulmonary artery and the right atrium/ventricle. [0107] The medical device 104 can comprise any elongate medical device insertable into the lumen of the introducer catheter, including but not limited to balloon angioplasty catheters, dilators, or thrombectomy devices. As shown in FIG. 9 A, the medical device 104 comprises a thrombectomy catheter with an elongate shaft 106 and an expandable element or funnel 108 on a distal end of the shaft. The funnel and/or shaft can include one or more lumens, e.g., an aspiration lumen and one or more fluid or irrigation lumens. The funnel can be advanced out of the distal end 103 of the introducer catheter and expanded within a target vasculature location to engage with clots during a thrombectomy procedure. The funnel is shown expanded or partially expanded in FIGS. 9A-9B for ease of illustration, however it should be understood that in various embodiments, the funnel can be carried by the introducer catheter in a collapsed or unexpanded state so as to reduce the profile of the funnel during delivery.

[0108] In FIG. 9A, a hub assembly 110 such as a Touhy Borst is shown which can provide access for the medical device 104 into the lumen of the steerable introducer catheter 102 and include an injection port for fluidic connection a fluid or contrast source 112. The injection port can direct the fluid or contrast into the lumen(s) of the introducer catheter. In the illustrated embodiment, the fluid or contrast source 112 can comprise a contrast injector configured to automatically or manually deliver a controlled volume (e.g., bolus) of a contrast agent into the patient’s vasculature via the introducer catheter 102. In some examples, injection of contrast from the injector into the hub assembly 110 provides the contrast agent into the annular space between the introducer catheter 102 and the medical device 104 (e.g., within the lumen of the introducer catheter, between the introducer catheter shaft and the shaft 106 of the medical device).

[0109] FIG. 9B shows the funnel 108 of the medical device 104 axially disposed out of a distal end 103 of the introducer catheter 102. In this example, contrast delivered by the fluid or contrast source 112 into the lumen of the introducer catheter can still be delivered into the patient, even when the balloon is in an inflated state. In some examples, the balloon can disperse the contrast agent as it’s delivered past the balloon from the introducer catheter. Alternatively, a dilator device or other medical device can be inserted into the introducer catheter, as will be described below.

[0110] The fluid or contrast source 112 (e.g., contrast injector) can be configured to automatically inject or deliver selected volumes or boluses of any contrast agent into the thrombus removal system to assist with imaging of the thrombus removal device and/or a target thrombus. In some embodiments, while the volumes and timing of contrast to be delivered by the injector are selected by a user or pre-selected, the injector can be configured to automatically and/or continuously deliver contrast at the selected volumes and frequency. In the illustrated embodiment, the fluid or contrast source can comprise a cradle assembly configured to receive one or more contrast injection syringe(s). The cradle assembly can include an automatic pusher or other mechanism configured to engage with the syringe to inject a contrast agent into the lumen(s) of the introducer catheter.

[OHl] The system 100 can employ control algorithms or protocols to provide consistent or controlled injection of fluid or contrast agent near the distal end of the introducer catheter. In some embodiments, the fluid or contrast source can be configured to inject a predetermined or pre-selected bolus or volume of fluid or contrast agent into the patient at the target location within the vasculature. For example, the fluid or contrast source may be configured to deliver a bolus of contrast agent (e.g., a 5ml bolus or “shot” of contrast) at a pre-determined time interval (e.g., every 3-5 seconds).

[0112] FIGS. 9C-9D are additional embodiments of an introducer catheter with further details on the sensors and locations to enable calculation of cardiac index or cardiac output. Generally, the catheters of FIGS. 9C and 9D both include features that enable measurement of oxygen saturation, pressure, flow, and thermodilution.

[0113] The embodiment of FIG. 9C includes a proximal port or sensor 114 and is configured to be placed in the right atrium. It can be, for example, approximately 30 cm from the tip of the catheter for placement within the right atrium when the tip is in the pulmonary artery. When this is a proximal port, it can be used for infusion and can also be used to assess central venous pressure (CVP) and right atrial pressure. In some examples, it is simply a proximal pressure sensor.

[0114] The embodiment of FIG. 9C can further include an infusion port 116, just proximal to the proximal port or sensor 114 (e.g., approximately 31 cm from the tip of the catheter for placement in the right atrium when the tip is in the pulmonary artery. This port is used for infusion of a heated or cooled fluid into the atrium to calculate a thermodilution curve. A distal port or sensor 118 is positioned at the tip of the catheter and can be used for measurement of the pulmonary artery pressure as fluid (e.g., cold fluid) is injected into the bloodstream from the infusion port 116. In some aspects, when this is a port, mixed venous can be drawn from this port in addition to the pressure sensing capabilities.

[0115] Thermistor or temperature sensor 120 can be a temperature-sensitive wire that terminates a short distance (e.g., 4 cm) proximal from the tip of the catheter. In some aspects, the thermistor can include a thermistor bead which rests in a main pulmonary artery when the catheter tip is positioned correctly. The connection of the thermistor port to a cardiac output (CO) monitor allows determination of a CO using thermodilution., it flows downstream and passes the tip of the catheter including the thermistor, allowing for a drop in the blood temperature to be recorded. This information can be used to plot a thermodilution curve. Additional measured or known parameters of the patient, including the patient's body mass index (size); core temp, Systolic, diastolic, central venous pressure CVP (measured from the atrium by the catheter) and pulmonary artery pressure are input to calculate a comprehensive flow vs pressure map.

[0116] As described above, the catheter can include an inflatable member or balloon 107 for holding the catheter in place when measuring cardiac output or index.

[0117] The introducer catheter can further include a fiber optic sensor 122 configured to provide instant readings of SvO2 or oxygen saturation of the ventricle tissues. When the proximal port or sensor 114 is positioned in the right atrium, the fiber optic sensor 122 is placed in the right ventricle.

[0118] In the embodiment of FIG. 9D, a heating coil 124 replaces the infusion port from the embodiment of FIG. 9C. This eliminates the cold fluid bolus, and instead directly heats the blood for measurement by the tip thermistor and thermodilution calculations.

[0119] In some aspects, one or more of the sensors or features described above can be placed on the medical device (e.g., thrombectomy catheter) instead of on the introducer catheter. For example, one or more of the tip thermistor, distal port or sensor, or fiber optic sensor can be placed on the medical device. Thermodilution can then be calculated by combining the functionality of the introducer catheter and the medical device (e.g., infusing cold fluid or heating blood with the introducer catheter, and then measuring the thermodilution (and pulmonary artery pressure) with the thermistor and pressure sensor on the medical device.

[0120] FIG. 10 illustrates a system that includes an introducer catheter (1) inserted into the right atrium and right ventricle of a heart, and a medical device (2) such as a thrombectomy catheter advanced out of the introducer catheter and extending into the pulmonary artery. This system can include the Swan-Ganz functionality described above. [0121] In the illustrated example, the introducer catheter can include a fiber optic sensor (3) for measuring SvO2, and an infusion port (4) for cold saline or fluid delivery. A thermistor (5) on the medical device can measure the temperature of flowing blood including the cold infusion to calculate thermodilution. Although the thermistor is shown on the medical device in this embodiment, as described above the thermistor can be on a distal tip of the introducer catheter and placed within the pulmonary artery. As also described above, the infusion port can be swapped for a heated coil which can also be used to calculate thermodilution.

[0122] As one of skill in the art will appreciate from the disclosure herein, various components of the thrombus removal systems described above can be omitted without deviating from the scope of the present technology. As discussed previously, for example, the present technology can be used and/or modified to remove other types of emboli that may occlude a blood vessel, such as fat, tissue, or a foreign substance. Further, although some embodiments herein are described in the context of thrombus removal from a pulmonary artery, the disclosed technology may be applied to removal of thrombi and/or emboli from other portions of the vasculature (e.g., in neurovascular, coronary, or peripheral applications). Likewise, additional components not explicitly described above may be added to the thrombus removal systems without deviating from the scope of the present technology. Accordingly, the systems described herein are not limited to those configurations expressly identified, but rather encompasses variations and alterations of the described systems. Conclusion

[0123] The above detailed description of embodiments of the technology are not intended to be exhaustive or to limit the technology to the precise forms disclosed above. Although specific embodiments of, and examples for, the technology are described above for illustrative purposes, various equivalent modifications are possible within the scope of the technology as those skilled in the relevant art will recognize. For example, although steps are presented in a given order, alternative embodiments may perform steps in a different order. The various embodiments described herein may also be combined to provide further embodiments.

[0124] From the foregoing, it will be appreciated that specific embodiments of the technology have been described herein for purposes of illustration, but well-known structures and functions have not been shown or described in detail to avoid unnecessarily obscuring the description of the embodiments of the technology. Where the context permits, singular or plural terms may also include the plural or singular term, respectively.

[0125] Unless the context clearly requires otherwise, throughout the description and the examples, the words "comprise," "comprising," and the like are to be construed in an inclusive sense, as opposed to an exclusive or exhaustive sense; that is to say, in the sense of "including, but not limited to." As used herein, the terms "connected," "coupled," or any variant thereof, means any connection or coupling, either direct or indirect, between two or more elements; the coupling of connection between the elements can be physical, logical, or a combination thereof. Additionally, the words "herein," "above," "below," and words of similar import, when used in this application, shall refer to this application as a whole and not to any particular portions of this application. Where the context permits, words in the above Detailed Description using the singular or plural number may also include the plural or singular number respectively. As used herein, the phrase "and/or" as in "A and/or B" refers to A alone, B alone, and A and B. Additionally, the term "comprising" is used throughout to mean including at least the recited feature(s) such that any greater number of the same feature and/or additional types of other features are not precluded. It will also be appreciated that specific embodiments have been described herein for purposes of illustration, but that various modifications may be made without deviating from the technology. Further, while advantages associated with some embodiments of the technology have been described in the context of those embodiments, other embodiments may also exhibit such advantages, and not all embodiments need necessarily exhibit such advantages to fall within the scope of the technology. Accordingly, the disclosure and associated technology can encompass other embodiments not expressly shown or described herein.

Claims

CLAIMS: What is claimed is:

1. A system for removing thrombus from a patient, the system comprising: an elongated catheter having at least one aspiration lumen configured to remove thrombus material; an aspiration mechanism fluidly coupled to the aspiration lumen and configured to reduce pressure in the aspiration lumen; a pressure sensor configured to monitor a pressure inside the aspiration lumen; a valve disposed between the pressure sensor and the aspiration mechanism; and an electronic controller operatively coupled to the aspiration mechanism, the pressure sensor, and the valve, the electronic controller being configured implement a clot hunting mode in which the electronic controller: 1) controls the valve to open; 2) controls the aspiration mechanism to pull a preset volume of fluid into the aspiration lumen; 3) after pulling the preset volume of fluid, controls the valve to close; 4) monitors a pressure response within the aspiration lumen to determine if a clot is engaged with the elongated catheter.

2. The system of claim 1, wherein the preset volume of fluid comprises 0-5ml.

3. The system of claim 1, wherein the preset volume of fluid comprises 5-10ml.

4. The system of claim 1, wherein the electronic controller monitors the pressure response within a preset time period.

5. The system of claim 4, wherein the preset time period comprises less than 1 second.

6. The system of claim 4, wherein the preset time period comprises less than 2 seconds.

7. The system of claim 4, wherein the preset time period comprises less than 3 seconds.

8. The system of claim 4, wherein the preset time period comprises less than 5 seconds.

9. The system of claim 1, wherein, if the electronic controller determines that clot is engaged with the elongated catheter, the electronic controller is further configured to: 5) control the valve to open, and 6) control the aspiration mechanism to aspirate clot into the aspiration lumen.

10. The system of claim 9, wherein a vacuum level applied during step 2 is lower than a vacuum level applied during step 6.

11. The system of claim 9, further comprising a fluid delivery mechanism configured to deliver one or more fluid streams into a distal end of the elongated catheter, wherein the system is further configured to control the fluid delivery mechanism to deliver fluid streams into the clot.

12. The system of claim 1, wherein, if the electronic controller determines that clot is not engaged with the elongated catheter, the electronic controller is further configured to: 5) control the valve to open, and 6) control the aspiration mechanism to return the preset volume of fluid to the patient.

13. A system for removing thrombus, the system comprising: an elongated catheter having at least one aspiration lumen configured to remove thrombus material; an aspiration mechanism fluidly coupled to the aspiration lumen and configured to reduce pressure in the aspiration lumen; a peristaltic pump coupled to the aspiration lumen; a pressure sensor configured to monitor a pressure inside the aspiration lumen; a valve disposed between the pressure sensor and the aspiration mechanism; and an electronic controller operatively coupled to the aspiration mechanism, the peristaltic pump, the pressure sensor, and the valve, the electronic controller being configured implement a clot hunting mode in which the electronic controller: 1) controls the peristaltic pump to pull a preset volume of fluid into the aspiration lumen; 2) after pulling the preset volume of fluid, monitor a pressure response within the aspiration lumen to determine if a clot is engaged with the elongated catheter.

14. The system of claim 13, wherein the preset volume of fluid comprises 0-5ml.

15. The system of claim 13, wherein the preset volume of fluid comprises 5-10ml.

16. The system of claim 13, wherein the electronic controller monitors the pressure response within a preset time period.

17. The system of claim 16, wherein the preset time period comprises less than 1 second.

18. The system of claim 16, wherein the preset time period comprises less than 2 seconds.

19. The system of claim 16, wherein the preset time period comprises less than 3 seconds.

20. The system of claim 16, wherein the preset time period comprises less than 5 seconds.

21. The system of claim 13, wherein, if the electronic controller determines that clot is engaged with the elongated catheter, the electronic controller is further configured to: 5) control the valve to open, and 6) control the aspiration mechanism to aspirate clot into the aspiration lumen.

22. The system of claim 21, wherein a vacuum level applied during step 2 is lower than a vacuum level applied during step 6.

23. The system of claim 21, further comprising a fluid delivery mechanism configured to deliver one or more fluid streams into a distal end of the elongated catheter, wherein the system is further configured to control the fluid delivery mechanism to deliver fluid streams into the clot.

24. The system of claim 13, wherein, if the electronic controller determines that clot is not engaged with the elongated catheter, the electronic controller is further configured to: 5) control the valve to open, and 6) control the aspiration mechanism to return the preset volume of fluid to the patient.

25. A method for removing thrombus, comprising: introducing a distal portion of an elongated catheter into the body of a patient, the catheter including an aspiration lumen in fluid communication with the distal end for removal of thrombus; positioning a distal end of the catheter in the region of a target thrombus; pulling a preset volume of blood into the aspiration lumen; returning the preset volume of blood to the patient; during the pulling and/or returning steps: closing or opening a valve in the aspiration lumen; monitoring pressure at least in the aspiration lumen; and identifying engagement of the target thrombus with the distal end based on the monitored pressure and a valve state of the valve.

26. The method of claim 25, wherein the preset volume of fluid comprises 0-5ml.

27. The method of claim 25, wherein the preset volume of fluid comprises 5-10ml.

28. The method of claim 25, further comprising monitoring the pressure over a preset time period.

29. The method of claim 28, wherein the preset time period comprises less than 1 second.

30. The method of claim 28, wherein the preset time period comprises less than 2 seconds.

31. The method of claim 28, wherein the preset time period comprises less than 3 seconds.

32. The method of claim 28, wherein the preset time period comprises less than 5 seconds.

33. The method of claim 25, wherein, if it is determined that the target thrombus is engaged, closing the valve, and aspirating the target thrombus into the aspiration lumen.

34. The method of claim 25, wherein, if it is determined that the target thrombus is not engaged, opening the valve, and returning the preset volume of blood to the patient.

35. A method of calculating cardiac output, comprising: advancing a sheath or introducer catheter into the pulmonary vasculature of a patient; introducing a bolus of cold fluid into the heart and measuring a temperature response at a distal tip of the introducer catheter; measuring pressures in the heart and the pulmonary artery; calculating cardiac output or index.

36. The method of claim 35, comprising measuring the temperature response with the introducer catheter.

37. The method of claim 35, comprising measuring the temperature response with a medical device advanced out of the introducer catheter.

38. An introducer catheter system, comprising: an elongate, steerable introducer catheter shaft adapted for insertion into a pulmonary artery of a subject; an infusion port adapted to be disposed within the heart when a tip of the shaft is in the pulmonary artery, the infusion port being configured to infuse a bolus of fluid into the heart; at least one pressure sensor disposed on the catheter shaft, the pressure sensor being configured to continuously or periodically measure a pressure within the pulmonary artery and/or the heart; a fiber optic sensor configured to measure SvO2; a thermistor on a distal portion of the catheter shaft, the thermistor being configured to measure changes in blood temperature; and at least one controller configured to calculate at least one of thermodilution (flow), cardiac output, or cardiac index.

39. An introducer catheter system, comprising: an elongate, steerable introducer catheter shaft adapted for insertion into a pulmonary artery of a subject; a heated coil adapted to be disposed within the heart when a tip of the shaft is in the pulmonary artery, the heated coil being configured to heat blood in the heart; at least one pressure sensor disposed on the catheter shaft, the pressure sensor being configured to continuously or periodically measure a pressure within the pulmonary artery and/or the heart; a fiber optic sensor configured to measure SvO2; a thermistor on a distal portion of the catheter shaft, the thermistor being configured to measure changes in blood temperature; and at least one controller configured to calculate at least one of thermodilution (flow), cardiac output, or cardiac index.